UNITY-6G partners (F. Javed, J. Mangues-Bafalluy, E. Zeydan and L. Blanco) have just published the first project research paper in the IEEE Open Journal of the Communications Society. The paper titled “Trustworthy Reputation for Federated Learning in O-RAN Using Blockchain and Smart Contracts” explores how blockchain technology can enhance trust and transparency in Open Radio Access Network (O-RAN) environments and proposes a blockchain-based reputation mechanism that ensures accountability in Federated Learning (FL) by verifying the accuracy and integrity of model updates.
By integrating smart contracts and deploying the framework on a scalable Layer 2 blockchain (Polygon), the study presents a decentralized approach to improving collaboration and interoperability in multi-vendor O-RAN deployments. The work aligns with O-RAN’s architecture and highlights the potential of decentralized applications (DApps) and blockchain oracles for secure off-chain computations.
The full paper and implementation details are freely available online.
Abstract
Collaboration in Open Radio Access Network (O-RAN) infrastructures through Federated Learning (FL). Traditional O-RAN architectures and centralized machine learning approaches face challenges when integrating multi-vendor environments, primarily due to lack of trust, proprietary data concerns, and limited interoperability. Our solution transitions from implicit trust, where the reliability of contributions is assumed, to explicit trust, where reputation is verifiably established on-chain. We introduce a blockchain-based reputation mechanism that evaluates the accuracy, integrity, and quality of participants’ model updates within the FL process. Smart contracts automate critical tasks—such as participant registration, model update verification, and reputation scoring—ensuring that data inputs directly influence accountability in a tamper-proof, transparent manner. By deploying the framework on a scalable Layer 2 blockchain (Polygon) testnet and proposing the use of a blockchain oracle within this architectural framework for secure off-chain computations, this work focuses on a conceptual architectural approach by aligning with O-RAN’s architecture to propose and deploy a Decentralized Application (DApp) on the blockchain. The proposed framework emphasizes a conceptual design over performance optimization and is structured to naturally benefit from ongoing improvements in blockchain scalability, which may reduce latency and enhance operational efficiency over time. Smart contracts for crucial processes and reputation calculation are included within our proposed DApp. The implementation of this work is publicly accessible online.
About the authors
Farhana Javed is a researcher at the Services as Networks (SaS) Research Unit within the Centre Tecnològic de Telecomunicacions de Catalunya (CTTC) in Spain. Currently pursuing her Ph.D. at the Universitat Politècnica de Catalunya (UPC), her research revolves around the integration of Blockchain, Distributed Ledger Technologies (DLTs), and Web 3.0, particularly within telecommunication networks. She received the FPI Spanish grant in 2019, paving the way for her active involvement in numerous projects and publication of articles. Noteworthy among these projects are 5Growth, 5GREFINE, 6GDAWN, UNITY6G, and Progressus. She has made significant contributions to the 5Growth project, which strives to empower vertical industries such as Industry 4.0, Transportation, and Energy by implementing AI-driven automated 5G solutions. Additionally, Farhana leads a Work Package (WP) and Proof of Concept (PoC) in the Decentralized AI and Architectures for Massive Wireless Network Slicing Scalability and Sustainability in 6G (6GDAWN) project and actively participated in the Progressus Project, dedicated to highly efficient and trustworthy electronics, components, and systems for the next-generation energy supply infrastructure. Through these endeavors, she expands her research contributions in the field.
Josep Mangues-Bafalluy is the Research Director and Head of the Services as Networks (SaS) research unit at CTTC, where he also oversees its research infrastructures. He has published over 150 papers in international journals and conferences. Since 1997, he has participated in more than 40 research projects (EU, Spanish, Industrial) in various roles (including PI). Currently, he co-leads 5G/6G projects UNICO I+D 6G-BLUR and 6G-DAWN and leads the UNICO I+D Plaza6G project. Prior to joining CTTC, he was an assistant professor at UPC. His research interests include Cloud/Edge computing, telco cloud (including open RAN), DLT, and AI/ML-based network management automation and orchestration of disaggregated networks.
Engin Zeydan is a Senior Researcher in the Services as Networks (SaS) group at CTTC in Barcelona, Spain. He received his Ph.D. from the Department of Electrical and Computer Engineering at Stevens Institute of Technology, Hoboken, NJ, USA, in 2011 and M.S. and B.S. degrees from the Department of Electrical and Electronics Engineering at Middle East Technical University, Ankara, Turkey, in 2006 and 2004, respectively. Before joining CTTC in 2018, he worked as an R&D Engineer for Avea (a Turkish mobile operator) between 2011 and 2016, as a Senior R&D Engineer at Turk Telekomunikasyon A.S. between 2016 and 2018, and as a part-time instructor at the Electrical and Electronics Engineering Department of Ozyegin University between January 2015 and June 2018. Dr. Zeydan has been primarily responsible for carrying out European Commission and nationally funded research activities at CTTC, Turk Telekomunikasyon, and Avea. He is currently the Project Coordinator of the Horizon Europe UNITY-6G European Project (January 2025–December 2027). He was the Project Coordinator of the H2020 MonB5G European Project (November 2021–April 2023). He has also been involved in other European-level projects such as 5Growth (2019–2022) and Clear5G (as WP leader, 2017–2018), FP7 projects MOTO (as WP leader, 2012–2015) and CROWD (2014–2015) in collaboration with various industries and universities. He is the co-author of over 150 papers in international journals and conferences and holds 12 patents (11 granted by the Turkish Patent Institute and 1 granted under the European Patent Office). His research interests include telecommunications, data engineering/science, and network security.
Luis Blanco is a Senior Researcher at CTTC. He holds a Ph.D. and an M.Sc. in Telecommunications Engineering from the Polytechnic University of Catalonia (UPC), along with an M.Sc. in Research on ICT (MERIT) and an MBA. Additionally, he has completed two postgraduate degrees in Data Science and Quantitative Finance. Dr. Blanco has actively participated in more than 25 research projects funded by public and private entities, including EC and ESA-funded projects, as well as national and industrial projects. Furthermore, he has led multiple projects with European industry. His research interests focus on AI and optimization for wireless communications in beyond 5G and 6G, as well as TN-NTN integrated systems, with a special emphasis on the RAN.
